The details may be on a a EU type approval plate, and would look something like the following:

Format 1: E4*83R00*83R05*1234*01

This would signify

E4 EC directive and the number 4 denotes the Country in which the approval was issued

83R00 The number 83R00 signifies the original UN/ECE Emission Regulation and indicates that this approval is for exhaust emissions. The number will be present in all UN/ECE emission approval numbers

83R05 This number indicates the version of the EC emission directive to which the vehicle complies. This number is referenced against known tables to determine which level of emission the vehicle complies with. ie 83R05 indicates that vhicle complies with UN/ECE Regulation 83.05 with 83R04 denoting Regulation 83.04 and so on.

1234 This is the model specific approval number. It is not important for determining emissions level and will vary with vehicle

01 This is the number of the extension to the emission approval, and is not important for determining emission level and will also vary.

Format 2: E4 83RI - 052439

E4 The Upper Case E indicates compliance with EC Directive, and the number denotes the Country

83RI The number 83 preceding the "R" shows that the vehicle complies with the UN/ECE regulation 83 for emissions. The Roman Numerals I or II after the "R" may not be present but can in combination with the first 2 digits of the following number describe the exhaust emissions.

05 The first two digits of the next section indicate the ammendment of the UN/ECE R83 that the vehicle complies with (ie if it is 04 the vehicle complies with UN/ECE Regulation 83.04)

2439 The last four digits make up the model-specific approval number

The above does seem a bit complicated , but I would be very grateful if someone could have a look at the EU type designation plates under the bonnet and see if there are any similar numbers listed.

The Japan spec 50th's had the North America Spec exhausts (different silencers and different exit location to 'euro' 50ths which had a '90 Td5' type tail pipe)..........but I think the engine management was the same between Jap and Euro 50ths.

I no longer have my 50th, but I think in the back of the owners manuals is a Euro conformance number as you requested (somewhere near the back at a guess).

Perhaps one of the 'current' 50th owners that has the orginal owners manual could check?_________________Greg